Logic-based eDRAM using local interconnects to reduce impact of extension contact parasitics
View Patent ↗An electronic device includes an active layer located over a substrate with the active layer having a logic circuit and an eDRAM cell. The electronic device also includes a first metallization level located over the active layer that provides logic interconnects and metal capacitor plates. The logic interconnects are connected to the logic circuit and the metal capacitor plates are connected to the eDRAM cell. The electronic device additionally includes a second metallization level located over the first metallization level that provides an interconnect connected to at least one of the logic interconnects, and a bit line that is connected to the eDRAM cell. A method of manufacturing an electronic device is also included.
1. An electronic device, comprising:
an active layer located over a substrate, the active layer including a logic circuit and an eDRAM cell;
a first dielectric layer located on the active layer and a second dielectric layer located on the first dielectric layer;
a first metallization level located on the first dielectric layer, the first metallization level including first logic interconnect lines on the first dielectric layer and a capacitor on the first dielectric layer, wherein the first logic interconnect lines are connected to the logic circuit through first logic contacts passing through the first dielectric layer and first and second metal capacitor plates of the capacitor are separately connected to the eDRAM cell through capacitor contacts passing through the first dielectric layer; and
a second metallization level located on the second dielectric layer, the second metallization level including second logic interconnect lines on the second dielectric layer, wherein the second logic interconnect lines are connected to the logic circuit through second logic contacts passing though the second dielectric layer, and a bit line on the second dielectric layer that is connected to the eDRAM cell.
2. The electronic device recited in claim 1 , wherein the second logic contacts contact the first logic contacts through the first logic interconnect lines.
3. The electronic device recited in claim 1 , wherein the bit line is connected to the eDRAM cell through first eDRAM contacts that pass through the first dielectric layer and through second eDRAM contacts that pass through the second dielectric layer.
4. The electronic device recited in claim 3 , wherein the second eDRAM contacts directly contact the first eDRAM contacts.
5. The electronic device recited in claim 3 , wherein the first metallization level further comprises eDRAM interconnect lines on the first dielectric layer and the second eDRAM contacts contact the first eDRAM contacts through the eDRAM interconnect lines.
6. The electronic device recited in claim 5 , wherein at least one of the second eDRAM contacts contacting a corresponding one of the first eDRAM contacts through one of the eDRAM interconnect lines is laterally offset from the corresponding one of the first eDRAM contacts.
7. The electronic device recited in claim 1 , wherein at least one of the second logic contacts contacting a corresponding one of the first logic contacts through one of the first logic interconnect lines is laterally offset from the corresponding one of the first logic contacts.
8. The electronic device recited in claim 1 , further including a third dielectric layer located on the second dielectric layer, wherein the second logic contacts, and, second eDRAM contacts connecting the bit line to the eDRAM circuit, both extend through the second and third dielectric layers.
9. The electronic device recited in claim 1 , wherein the logic circuit includes a static random access memory (SRAM) or a logic network.
10. The electronic device recited in claim 1 , wherein the first and second logic interconnect lines provide a global interconnection between the logic circuit and a different logic circuit or the eDRAM cell or a different eDRAM cell.
11. The electronic device recited in claim 1 , wherein the capacitor plates span the second dielectric layer, and bottoms of each of the capacitor plates contact different ones of the capacitor contacts.
12. A method of manufacturing an electronic device, comprising:
providing an active layer located over a substrate, the active layer including a logic circuit and an eDRAM cell;
forming a first dielectric layer on the active layer;
forming a first metallization level on the first dielectric layer, the first metallization level including first logic interconnect lines on the first dielectric layer and a capacitor on the first dielectric layer, wherein the first logic interconnect lines are connected to the logic circuit and first and second capacitor plates of the capacitor are separately connected to the eDRAM cell through capacitor contacts passing through the first dielectric layer;
forming a second dielectric layer on the first dielectric layer; and
forming a second metallization level on the second dielectric layer, the second metallization level including second logic interconnect lines on the second dielectric layer, wherein the second logic interconnect lines are connected to the logic circuit through second logic contacts passing though the second dielectric layer, and a bit line on the second dielectric layer that is connected to the eDRAM cell.
13. The method recited in claim 12 , wherein the second logic contacts contact the first logic contacts through the first logic interconnect lines.
14. The method recited in claim 12 , wherein the bit line is connected to the eDRAM cell through first eDRAM contacts that pass through the first dielectric layer and through second eDRAM contacts that pass through the second dielectric layer.
15. The method recited in claim 14 , wherein the second eDRAM contacts directly contact the first eDRAM contacts.
16. The method recited in claim 14 , wherein forming the first metallization level further includes forming eDRAM interconnect lines on the first dielectric layer, wherein the second eDRAM contacts contact the first eDRAM contacts through the eDRAM interconnect lines.
17. The method recite in claim 16 , wherein at least one of the second eDRAM contacts contacting a corresponding one of the first eDRAM contacts through one of the eDRAM interconnect lines is laterally offset from the corresponding one of the first eDRAM contacts.
18. The method recited in claim 12 , wherein at least one of the second logic contacts contacting a corresponding one of the first logic contacts through one of the first logic interconnect lines is laterally offset from the corresponding one of the first logic contacts.
19. The method recited in claim 12 , further including forming a third dielectric layer on the second dielectric layer, wherein the second logic contacts, and, the second eDRAM contacts connecting the bit line to the eDRAM circuit, both extend through the second and third dielectric layers.
20. The method recited in claim 12 , wherein the logic circuit includes a static random access memory (SRAM) or a logic network.
21. The method recited in claim 12 , wherein the first and second logic interconnect lines provide a global interconnection between the logic circuit and a different logic circuit or the eDRAM cell or a different eDRAM cell.
22. The method recited in claim 12 , wherein the capacitor plates span the second dielectric layer, and bottoms of each of the capacitor plates contact different ones of the capacitor contacts.